Design and Optimization of Microalgal Systems for Direct Air CO₂ Capture: Emerging Strategies for Sustainable Carbon Removal

Abstract

In recent years, we have experienced significant increases in greenhouse gas emissions and with this, we
face grave consequences worldwide. Transitioning to renewable energy is essential but to be fully effective
at reducing GHG emissions from very hard to decarbonise industries, deployment of additional
technologies like carbon capture technology will also be required. Microalgal growing systems are another
viable carbon capture technology due to their very high capture rates and ability to grow in many different
types of conditions. Microalgal growing systems have a lot of potential to mitigate climate change and are
an effective and sustainable method of sequestering CO2 on a large scale. Therefore, in order to optimize
microalgae's CO2 capture efficiency, key factors such as light levels, pH, temperature, availability of
nutrients and strain selection must be considered. Photobioreactors with advanced configurations, including
flat-plate designs with PIAT internals and sequential-flow bubble column reactors, will have greater CO2
absorption and biomass productivity than traditional photobioreactors. The reduction of CO2 in the
atmosphere globally can be facilitated by successfully resolving key issues related to reactor optimization,
CO2 delivery, and strain performance of microalgae, complemented by genetic engineering and the
application of carbonic anhydrase enzymatic solutions. For this reason, continuous research and innovation
are critical to realizing the benefits of microalgae for climate change mitigation and as a potential green and
renewable means of advancing to a sustainable future. This research project examines optimization methods
for algal systems for effective direct air capture (DAC) from biological, technological, and economic
perspectives